CMP0186

.. versionadded:: 4.1

Regular expressions match ^ at most once in repeated searches.

This policy affects commands that perform multiple regular expression searches:

:command:string(REGEX MATCHALL)
:command:string(REGEX REPLACE)
:command:list(TRANSFORM REPLACE)

and the generator expression :genex:$<LIST:TRANSFORM,list,REPLACE>.

CMake 4.0 and below match the ^ anchor at the start of every successive search, leading to multiple matches:

.. code-block:: cmake

string(REGEX REPLACE "^a" "b" result "aaaa") # result="bbbb" string(REGEX MATCHALL "^a" result "aaaa") # result="a;a;a;a"

CMake 4.1 and above prefer to match the ^ anchor at most once, at the start of the input string:

.. code-block:: cmake

string(REGEX REPLACE "^a" "b" result "aaaa") # result="abbb" string(REGEX MATCHALL "^a" result "aaaa") # result="a"

This policy provides compatibility for projects that have not been updated.

The OLD behavior for this policy is to match ^ multiple times, at the start of each search. The NEW behavior for this policy is to match ^ at most once, at the start of the input string.

.. |INTRODUCED_IN_CMAKE_VERSION| replace:: 4.1 .. |WARNS_OR_DOES_NOT_WARN| replace:: does not warn .. include:: include/STANDARD_ADVICE.rst

.. include:: include/DEPRECATED.rst